LAMELLIBRANCHIATA OF THE LOWER MARLS. 61 



Geaus PLICATULA Lam. 

 Flicatula urticosa. 

 Plate IX, Figs. 1 and 2. 

 Ostrca urticosa, Morton. Syuop., 1st ed. 



PUcatiila urticosa, Mortou. Syuop., p. G2, PI. X, V\g. 2. Am. Jour. Sci., Vol. XXIV, 1st 

 ser., PI. X, Fig. 2. Gabb, Syuop., p. 1G9. Meek, Check-list, p. 7. Geol. 

 Surv. N. J., 1868, p. 724. Stoliczka and others. 



Shell irregularly oval in outline and obliquely curved, biconvex or 

 plano-convex, mai-ked by strong, somewhat angular radiating and bifur- 

 cating plications, usually much stronger and less numerous on the lower 

 than on the upper valve, and crossed by strong projecting concentric 

 lamella, which are elevated and often form thin, flat spines on the crest of 

 the radiating plications of greater or less length, which give a very rough 

 and spiney surface to the shell, resembling that of Spondylus. Muscular 

 impi'ession moderate; teeth not observed. 



On some internal casts from Freehold the muscular scar is quite large, 

 and, so far as can be judged, the teeth have been quite small. The shell 

 appears to have been quite abmidant, and to have grown in groups, attached 

 to each other or to foreign bodies. On the Alabama specimens, and on 

 some of those from New Jersey, there are indistinct radiating strise between 

 the plications. The largest individuals which I have observed are casts, 

 one of which is one inch and five-eighths long and of a broadly-ovate form. 



Formation and locality. — In the Lower Green Marls at Freehold and 

 Holmdel, N. J. The type specimens of Dr. Morton in the collection of the 

 Academy' of Natural Sciences, Philadelphia, are without locality, being- 

 marked "Lower Cretaceous, N. Jersey" only. 



Geuus RADULA Klein. 



Radula pelagica. 



Plate IX, Figs. 3-5. 



Plagiostoma pelagica Mort. Syuop., p. 61, PI. V, Fig. 2. 



Ctenoides pelagica [MoTt.) Gabh. Synop. Cret. Form., p. 111. Conrad, J. A. N. S., 



Vol. IV, p. 276. 

 Lima xyelagica (Mort.) Meek. Check-list Smith. Inst., p. 7. 

 Badula pelagica (Mort.) Stoliczka. Palteont. ludica. Vol. Ill, p. 416. 

 E. pelagica (Mort.) Meek. Geol. Surv. K J., 1868, p. 724. 



Shell of small size, seldom measuring more than one and a half inches 

 in its greatest length from beaks to base; very oblique, strongly ovate, 



